Hitherto, in a gas supply system of a semiconductor manufacturing apparatus or the like, to control a flow rate of gas, for example, a thermal-type mass flow controller, a sonic-type flow controller, a Coriolis-type flow controller, an impeller-type flow controller, an ultrasonic-type flow controller, a Karman's vortex type flow controller, or the like is used.
To control the flow rate of gas by using any of them, however, there are many restrictions such as (1) necessity of forceful suppression of a turbulent flow of gas, (2) necessity of providing a measurement device in some midpoint of a channel of the gas, and (3) necessity of regulation of pressure of the gas.
The present invention relates to, therefore, a flow controller and a flow controlling method achieved to solve the problem and its object is to release the flow controller and the flow controlling method from the conventional restrictions by using a novel type called a pulse shot type.